The objective of this project is to evaluate and implement new methodology whenever it offers an advantage to recovery of microorganisms from cancer patient samples and to develop and standardize methods for performing accurate susceptibility tests including those involving newly developed antimicrobial agents. Tests enabling the detection of Cryptococcus neoformans antigen in the serum and cerebrospinal fluid of cancer patients is now available on a routine basis. A system has been set up to determine phage-types of S. aureus recovered from patients, personnel and environment. An evaluation of questionable or weakly positive coagulase tests for S. aureus is also being done to confirm recent reports in literature that these questionable reactions should not be considered positive. Due to a low yield of viruses from viral cultures, a new system of direct tissue culture inoculation is now being utilized and is being compared to the previous viral holding broth. A new schema has been devised for the differentiation and identification of the saccharolytic pseudomonas other than P. aeruginosa. We are presently attempting to determine the applicability of its determinations under routine use.